fastBinaryJSON

• Download fastBinaryJSON_v1.0.zip
• Download fastBinaryJSON_v1.1.zip
• Download fastBinaryJSON_v1.2.zip 
• Download fastBinaryJSON_v1.3.zip
• Download fastBinaryJSON_v1.3.1.zip 
• Download fastBinaryJSON_v1.3.2.zip
• Download fastBinaryJSON_v1.3.3.zip 
• Download fastBinaryJSON_v1.3.4.zip
• Download fastBinaryJSON_v1.3.5.zip 
• Download fastBinaryJSON_v1.3.7.zip

Preface 

The code is now on CodePlex under Git source control (http://fastbinaryjson.codeplex.com/).

Introduction 

fastBinaryJSON is based on my fastJSON article (http://www.codeproject.com/Articles/159450/fastJSON) and code which is a polymorphic object serializer. The main purpose for fastBinaryJSON is speed in serializing and deserializing data for the use in data transfer and storage to disk. It was created for my upcoming RaptorDB -  Document Database engine, for performance.

Features

fastBinaryJSON has the following feature list: 

• Based on fastJSON code base (very fast, polymorphic)
• Supports : HashTables, Dictionary, Generic Lists, Datasets, ...
• Typically 2-10% faster on serialize, 17%+ faster on deserialize. 

Why?

Why another serializer you may ask, why not just use fastJSON? The answer to this is simple : performance. JSON while a great format has the following problem:

• JSON is a text format, so you loose type information on serializing which makes deserializing the data again time consuming. 

Why not BSON?

Why not just use BSON (http://bsonspec.org/) you may ask? The answer is the following:

• Looking at the specifications on the above site, you feel overwhelmed as it is hard to follow.
• You feel that the specs have evolved over time and a lot of the coding parts have been deprecated.
• BSON encodes lengths into the stream which inflate the data, this might be fine for the use case the authors envisioned, but for data transfer and storage it just makes things larger than they need to be.
• Because of the length prefixes, the encoding of the data object must be done in two passes, once to output the data, and a second time to set the length prefixes.
  

I initially started off by doing a BSON conversion on fastJSON but it got too complicated, so it was scrapped.  

How is data encoded in fastBinaryJSON?  

JSON is an extremely simple format, so fastBinaryJSON takes that simplicity and add the needed parts to do binary serialization. fastBinaryJSON follows the same rules as the JSON specification (http://json.org) with the following table showing how data is encoded: 

As you can see  from the above all the encoding rules are the same as JSON and primitive data types have been given 1 byte tokens for encoding data. So the general format is :

TOKEN,  { DATA } : where DATA can be 0 or more bytes

Strings can be encoded in 2 ways, as UTF8 or Unicode, where UTF8 is more space efficient and Unicode is faster.

String keys or property names are encoded as a special UTF8 stream which is limited to 255 bytes in length to save space (you should not have a problem with this as most property names are short in length).

Performance tests

To get a sense of the performance differences in fastBinaryJSON against fastJSON the following tests were performed, times are in milliseconds, each test was done on 1000 objects and repeated 5 times, the AVG column is the average of the test excluding the first which is skewed by initialization times:

As you can see in the DIFF column which is [ fastJSON / fastBinaryJSON ] the serializer performs at least 2% faster  and the deserializer at least 17% faster, with the greatest difference being with DataSet types which are a lot of rows of data.

Using the code 

To use fastBinaryJSON you can use the following code samples:

byte[] bytes = fastBinaryJSON.BJSON.Instance.ToJSON(obj);
byte[] bytes = fastBinaryJSON.BJSON.Instance.ToJSON(obj, true, true); // optimized dataset, unicode strings

object obj = fastBinaryJSON.BJSON.Instance.ToObject(bytes);
SalesInvoice obj = fastBinaryJSON.BJSON.Instance.ToObject<SalesInvoice>(bytes); // type is known 

There are 3 parameters which control how the serialization is done which can be set on the Instance or can be done by a per call basis like the above examples :

History    

• Initial Release : 25^th March 2012 
• Update : 26^th March 2012
• Added link to codeplex source control
• Update v1.1 : 26^th May 2012
• bug fix datetime to local time
• added BJSONParameters
• added global types (reverse format from fastJSON to overcome size limits on name strings)
• Update v1.2 : 24^th July 2012
• refactored reflection code into Reflection class
• added support for top level struct object serialize/deserialize 
• Update v1.3 : 11^th August 2012
• bug fix reflection code
• added unit tests
• changed ArrayList to List<object>
• updated code to be similar to fastJSON
• deserialize ToObject< Dictionary<T,V> > 
• deserialize ToObject< List<T> >
• added FillObject method
• Update v1.3.1 : 16^th August 2012
• bug fix $types and arrays
• optimize writing $types 
• Update v1.3.2 : 7^th September 2012
• null object serialize fixed
• added sealed keyword to classes
• bug fix SerializeNullValues=false and an extra comma at the end
• FillObject nested types
• Update v1.3.3 : 17^th September 2012 
• bug fix deserialize zero length arrays
• test for German locale numbers
• Update v1.3.4 :  20^th September 2012
• singleton uses ThreadStatic for concurrency (thanks to Philip Jander)
• bug fix extra comma in the output when only 1 property in the object (thanks to Philip Jander)
• Update v1.3.5 :  16^th November 2012  
• added support for root level DataSet and DataTable deserialize (you have to do ToObject<DataSet>(...) )
• added dataset tests
• added MonoDroid project
• Update v1.3.7 : 20^th April 2013
• customtype is now builtin
• added UseUTCTimes property for datetime
• switched to properttype enum instead of booleans
• using switch instead of linked if statements
• unified DynamicMethod between silverlight and full .net
• SafeDictionary lock fixes